package com.atguigu.juc;

import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * @author admin
 *
 * 一、用于解决多线程安全问题的方式：
 *
 * synchronized：隐式锁
 * 1.同步代码块
 *
 * 2.同步方法
 *
 * jdk1.5 后：
 * 3.同步锁：Lock
 * 注意：是一个显式锁，需要通过 lock() 方法上锁，必须通过 unlock() 方法进行释放锁
 */
public class TestLock {

    public static void main(String[] args) {
        Ticket ticket = new Ticket();

        new Thread(ticket, "1号窗口").start();
        new Thread(ticket, "2号窗口").start();
        new Thread(ticket, "3号窗口").start();
    }
}

class Ticket implements Runnable {

    private int tick = 100;

    private Lock lock = new ReentrantLock();

    @Override
    public void run() {
        while (true) {
            /*
            上锁
             */
            lock.lock();

            try {

                if (tick > 0) {
                    try {
                        Thread.sleep(200);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    System.out.println(Thread.currentThread().getName() + " 完成售票，余票为：" + --tick);
                }
            } finally {
                /*
                释放锁
                 */
                lock.unlock();
            }
        }
    }
}
